Answer:
Step-by-step explanation:
From the picture attached,
Addition of the blocks in first row is 60
a + a + a + 12 = 60
3a + 12 = 60
3a = 60 - 12
3a = 48
a = 16
For second row,
(b + 5) + (b + 5) + (b + 5) + (b + 5) = 60
4(b + 5) = 60
b + 5 = 15
b = 10
For third row,
(a + b) + c = (b + 5) + (b + 5) + (b + 5)
a + b + c = 3(b + 5)
16 + 10 + c = 3(10 + 5) [Since, a = 16 and b = 10}
26 + c = 45
c = 45 - 26
c = 19
For fourth row,
3c + d = 60
3(19) + d = 60
57 + d = 60
d = 60 - 57
d = 3
